Castorbean Production as Related to Length of Growing Season I. Effect of Date of Plant Desiccation¹

Abstract

Castorbean plants (Ricinus communis L.) were killed by chemical desiccant at weekly intervals during the fall in four tests in 2 years in Nebraska. Effects of desiccation on total yield and germination were determined. Yield, weight per 100 seeds, and germination were also determined for sequential racemes. Natural freeze was the check treatment. Yield increased at a uniform rate with delay of desiccation except in one test severely affected by Alternaria leaf spot disease. The average weekly increase in yield for the four tests was 199 kg per ha. Primary racemes were mature at the time of first treatments. The contribution of secondary, tertiary and quaternary racemes to yield increased during the entire course of the treatments. Seed weight from secondary and tertiary racemes increased with maturity. Germination was positively and significantly correlated with seed weight. The highest percentage germination was obtained from late September and early October desiccation treatments. Freezing of immature seeds and weathering of mature seeds reduced germination. Drying of seed following plant desiccation required about 10 days and did not reduce germination. Yield loss from 10 days' growth prior to freeze was calculated to be 284 kg per ha. On basis of low seed germinations obtained in these tests, the feasibility of castorbean production for seed in Nebraska would be questioned.

Improving Quantity and Quality of Castor Bean Oil for Biofuel Growing under Severe Conditions in Egypt

“…The increase in oil yield which was obtained by the increment of K-amino levels might be due to the role of K fertilizer and amino growth regulator in stimulating vegetative growth and keeping the flowers on the trees [10]. These values are in line with previously reported by many authors [11][12][13][14][15][16].…”

Chemical Desiccation Experiments with Hard Red Spring Wheat, Triticum aestivum L.1

“…Chemicals have been successfully applied as pre-harvest desiccants to sorghum (Sorghum bicolor (L.) Moench) (4), alfalfa (Medicago sativa L.) (3), castorbeans (Ricinus) (5,7), and other crops including soy• beans (Glycine max (L.) Merr. ), corn (Zea mays L.), cotton (Gossypium), rice (Oryza sativa L.), potatoes (Solanum tuberosum), and tomatoes (Lycopersicum) (1).…”

Urea Fertilization: Effects on Growth, Nutrient Uptake and Root Development of the Biodiesel Plant, Castor Bean (Ricinus communis L.)

“…Castor plant is generally produced from seed and the time from planting to emergence was found to vary between 7 -23 days, depending on soil temperature [7] [3] [8] [9] [10] and as well as regeneration by tissue culture, to receive disease free, large number of planets for commercial cultivation. Regeneration by tissue culture technique would also be a feasible alternative for improving the quality and to develop an efficient protocol for propagation of castor oil plant [11] [12] [13] [14] [15].…”

“…98-284 passed by Congress in 1984 [24]. Castor bean yield in the US, however, dependent on the latitude and management practices [10] [25]; maximum yield reported was 2690 kg ha−1 in southern Nebraska under irrigated conditions [26]. In a recent planting date and location study in the US south-central region showed that castor bean mean yields were greatest at Memphis, TN, the northern most location (maximum, 1954 kg ha−1 ) and lowest at Poplarville, MS, the southernmost location [27].…”